The FBI let Apple reveal the existence of a single secret inquiry

Although Apple famously resisted the FBI when it wanted Apple to create a tool to break into the San Bernardino iPhone, most of the time when police come to Apple with proper authorization, it says yes.

Apple's latest report, published on Monday, has been significantly bolstered with additional disclosures and statistics about the second half of 2016.

One thing is clear: the report indicates that Apple saw a significant increase in requests for its data for the second half of 2016. National security requests went up from around 3,000 in the first half of 2016 to about 6,000 in the second half.

In addition, given the proper legal authorization, Apple usually complies with requests— for example, in the second half of last year, Apple provided details 78% of the time, or 3335 out of 4254 US requests for information related to which Apple account is connected to an iPhone.

Apple also started publishing details about requests for data from non-government entities in the United States. One example could be in a divorce proceeding, if one party wanted to pull iMessage information from Apple to bolster its case. Apple received 157 of these requests in the second half of 2016, and rejected 71% of them.

A secret letter

Apple also revealed in its report that it received one declassified national security letter during the period. A national security letter is a controversial request for records enabled by the USA Freedom Act, which is the successor to the Patriot Act.

The key to national security letters, commonly referred to as NSLs, is the government says they must be kept secret — Apple can't even tell the person whose data it's pulling that it's under investigation, because the request is related to national security purposes.

Under the USA Freedom Act, which was passed in 2015, the FBI goes back and looks at its NSLs and decides which of them need to remain classified, and sometimes decides to declassify certain letters. That's what happened here and why Apple included the line item in its recent report.

The first declassified NSLs started going out last summer.

Apple has many other NSLs it still has to keep secret, thousands, according to previous transparency reports, because the FBI declined to declassify them.

Apple did not provide additional details about the national security letter in its report, such as who it was targeted at or what kind of information it was seeking, and a representative declined to comment to ZDNet, which first reported the national security letter.

Theoretically, because the letter is now declassified, it could be published and its details made public, but Apple hasn't done that. Apple declined to comment for this story.

But although Apple does frequently work with law enforcement, it emphasizes in the report that it hasn't given a "back door" or provided bulk data to any government. "To date, Apple has not received any orders for bulk data," according to the report.